Processes for the detection of optical signals are basically known. For example, light modules of illuminating devices have additional detectors in order to detect optical signals. For example, a feedback concerning a reflected amplitude from such a detector can be recognized. If an illumination area is defined for an illuminating device, it may be useful to obtain a feedback concerning the illumination situation. Based on this feedback the illumination can be adjusted, so that, e.g., individual shadows can be compensated by shadowing objects. Separate detectors, which can detect the optical signals, especially the light emitted by other light sources, are necessary for this in prior-art light modules.
The drawback of prior-art processes and prior-art light modules is that the detection must be carried out by additional components in the form of additional detectors. These require additional space for their installation, as a result of which the overall size of prior-art light modules is increased. In addition, additional components in the form of detectors lead to additional costs and additional expenses for materials. Another drawback arises because the additional detectors do not have exactly the same optical viewing direction, which may be especially disturbing in case of close objects.